#ifndef __RBTREE_H__
#define __RBTREE_H__
#include <cnix/kernel.h>

struct rb_node
{
  unsigned long  rb_parent_color;
#define RB_RED    0
#define RB_BLACK  1
  struct rb_node *rb_right;
  struct rb_node *rb_left;
} __attribute__((aligned(sizeof(long))));

struct rb_root
{
  struct rb_node *rb_node;
};

#define rb_entry(ptr, type, member) container_of(ptr, type, member)
#define rb_parent(r)   ((struct rb_node *)((r)->rb_parent_color & ~3))
#define rb_color(r)   ((r)->rb_parent_color & 1)
#define rb_is_red(r)   (!rb_color(r))
#define rb_is_black(r) rb_color(r)
#define rb_set_red(r)  do { (r)->rb_parent_color &= ~1; } while (0)
#define rb_set_black(r)  do { (r)->rb_parent_color |= 1; } while (0)

static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p)
{     
  rb->rb_parent_color = (rb->rb_parent_color & 3) | (unsigned long)p;
}       
static inline void rb_set_color(struct rb_node *rb, int color)
{         
  rb->rb_parent_color = (rb->rb_parent_color & ~1) | color;
}         
          
#define RB_ROOT (struct rb_root) { NULL, }
#define rb_entry(ptr, type, member) container_of(ptr, type, member)
      
#define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL)
#define RB_EMPTY_NODE(node) (rb_parent(node) == node)
#define RB_CLEAR_NODE(node) (rb_set_parent(node, node))
        
extern void rb_insert_color(struct rb_node *, struct rb_root *);
extern void rb_erase(struct rb_node *, struct rb_root *);
        
/* Find logical next and previous nodes in a tree */
extern struct rb_node *rb_next(const struct rb_node *);
extern struct rb_node *rb_prev(const struct rb_node *);
//extern struct rb_node *rb_first(const struct rb_root *);
//extern struct rb_node *rb_last(const struct rb_root *);

static inline void rb_link_node(struct rb_node * node, struct rb_node * parent,
        struct rb_node ** rb_link)
{   
  node->rb_parent_color = (unsigned long )parent;
  node->rb_left = node->rb_right = NULL;
  
  *rb_link = node;
}

#endif
